The NOAD lists the pronunciation of Xavier as
(ig)ˈzāvēər. In my own experience the parenthetical pronunciation is very common. I, however, do not know of any other x-initial words that are vowel-initiated when spoken.
Why is Xavier often pronounced
I have two guesses, but they are merely guesses.
While Xavier is pronounced
xaˈβjerin its native Spanish, it is pronounced
ɡzavjein French (Wikipedia). Does English pronunciation follow French pronunciation, but with the initial
ggrowing into a vowel?
According to Wikipedia the name Xavier comes from the Basque "etxe berri", for 'new house'. Did English somehow maintain the vowel from etxe?
What is the real reason Xavier is sometimes pronounced vowel-initial? Has this alternate pronunciation always existed? Are any other English x-initial words spoken with an initial vowel?